Hoses, conduits, pipes, and like fluid conveying systems are commonly used to convey a wide variety of different fluids from a source to a location of use. Many such fluid conveying systems have at least a portion thereof which is flexible to accommodate misalignment and/or relative movement between system components being connected. For example, fuel lines intended to convey gas fuels such as natural gas or the like, from a source to a use location are sometimes constructed to include at least one portion formed of flexible hose.
If the flexible portion is corrugated metal, it will have several advantages over other forms list of hose used to convey fluids, including an ability to move, expand and contract while remaining a secure fluid-tight structure. Moreover, as compared to several other forms of hose or conduit, corrugated hose is inexpensive to manufacture yet is structurally secure enough to be safely used in most gas flow situations. Therefore, installation of gas-fired appliances can be expedited because exact placement is not necessary and mis-placement caused by approximate positioning can be accommodated and corrected by a flexible gas line that is sufficiently secure for the purpose. Thus, gas lines can be permanently installed in a building and routed through the structure from a gas source to the general location of gas-fired equipment and appliances. Less permanent gas lines can then be used to make the final connections to the appliances themselves, and are commonly referred to as xe2x80x9cwhips,xe2x80x9d and are used to accommodate and correct mis-location caused by approximate positioning of an appliance. Gas line whips are commonly fabricated from lengths of corrugated, flexible metal hose. Whip gas lines are also commonly used with appliances which are subject to some degree of movement, such as gas-fired dryers, ovens and the like.
Even though gas line whips are flexible, they, like permanent gas lines require secure end connections. Design criteria common to such gas lines include providing secure, fluid-tight seals and providing sufficiently strong end connections to avoid a separation or pull-out of the line from the appliance or other equipment. In the case of a gas fuel line, leaks can be very dangerous since many gas fuels are by nature both toxic and highly flammable. Thus, to avoid accidental gas poisoning or explosion, structural security with such systems is very important.
Threaded fittings have been found to provide a coupling that is secure and leak-resistant enough for gas flow systems of the type used in most settings. In the case of rigid gas lines, sufficient material thickness is generally present to provide threaded fittings which are secure enough for the purposes associated with such settings. With corrugated flexible metal hose, however, the material is often relatively thin walled and thus not sufficiently thick to accommodate threading which is of a size sufficient to form a connection that is secure enough for the purposes of gas line connections in most systems.
Therefore, there is a need for a coupling system for a corrugated flexible hose with the advantages and features required for a secure connection of a corrugated hose to another element that is secure enough for connecting a gas line to that element.
To address the problem of providing secure fittings on a flexible metal hose, various coupling systems have been devised. These include a variety of compression fittings, washers, O-rings, and gaskets. Still further patents, such as U.S. Pat. No. 6,102,445, the disclosure of which is incorporated herein by reference, disclose a system for coupling a corrugated hose to another element. In particular, this incorporated patent discloses a coupling system for coupling a flexible metal hose with an annular or spiral corrugations to devices, such as a gas-fired appliance or a fuel source. The hose coupling system of the incorporated patent includes a fitting assembly with inner and outer fittings adapted for threaded interconnection on the end of the flexible hose. The inner fitting includes a bore which receives a washer assembly with an O-ring for forming a sealed connection, a backer ring and an expandable washer. The expandable washer is selectively received on the corrugations of the flexible hose and functions to retain the fitting and washer assemblies securely in place and to prevent pull-out of the coupling while providing a positive connection to the hose whereby the O-ring gasket can be compressed for an effective seal.
One form of the coupling system disclosed in FIGS. 9-11 of the incorporated patent couples the flexible hose to a wall or other such static structure. While effective, this form of the invention disclosed in the incorporated patent can be improved in several areas.
For example, the coupling system disclosed in the incorporated patent may require brazing and/or welding to complete the connection. While such steps effect a secure seal, they are often time-consuming and labor intensive. The extra steps and time associated with such steps may be expensive.
Therefore, there is a need for a sealed coupling system for corrugated flexible hose that can effect a secure seal between the hose and another element, such as a static structure, without requiring a step of brazing and/or welding.
Still further, the flexible hose often extends through an opening in a wall or other such static structure with the sealed coupling being located on one side of the wall and the hose being fed through the wall from the other side of the wall. This can create difficulties due to the hidden nature of some of the connections with respect to the other connections. Still further, if there is a problem with the part of the connection system that is located inside a wall after the system is in place, a great deal of labor and effort may be required to fix the problem.
Therefore, there is a need for a sealed coupling system for corrugated flexible hose that can effect a secure seal between the hose and another element, such as a static structure, without requiring hidden coupling elements.
Since some gas flow systems extend through a wall of a building, it is usually necessary to ensure that any opening in that wall is securely closed once the system is in place. This will prevent moisture and/or insects from invading the building through the opening. However, it is also necessary that such protection not be unduly expensive or difficult to install.
Therefore, there is a need for a sealed coupling system for corrugated flexible hose that can effect a secure seal between the hose and another element, such as a static structure while protecting the integrity of the finished coupling system and the static structure.
These and other objects are achieved by a sealed coupling system for corrugated flexible hose that includes a one-piece male/female termination fitting that mounts on a base plate to sealingly couple a flexible corrugated hose to a static structure, such as a wall or the like.
The sealed coupling system includes a gasket, a retainer ring and a slider ring to securely couple the flexible hose to the termination fitting in the manner described in the incorporated patent.
A stop element is also included to further secure the system in place in a manner that ensures the integrity of any static structure through which the corrugated hose extends. The stop plate also ensures the secure nature of the fitting system and is expeditiously mounted in place.
The sealed system of the present invention eliminates the need for welding and/or brazing because connections are effected using threadable connections. Still further, hidden fittings are eliminated because the transition fitting of the present invention can be securely mounted on a wall and has elements that can be securely connected to the hose and to other elements mounting the hose on the wall which can be located on one side of the wall while the hose extends through the wall from the other side.
The present invention relates to the general field of pipe couplings and joints, and to the particular area of corrugated hoses and couplings therefor.
It is a main object of the present invention to improve the coupling system disclosed in the incorporated document, U.S. Pat. No. 6,102,445.
It is another object of the present invention to provide a coupling system for corrugated flexible hose which can securely connect that hose to a static structure without the need of brazing and/or welding.
It is another object of the present invention to provide a coupling system for corrugated flexible hose which can securely connect that hose to a static structure without the need of hidden fittings.
It is another object of the present invention to provide a sealed coupling system for corrugated flexible hose that can effect a secure seal between the hose and another element, such as a static structure while protecting the integrity of the finished coupling system and the static structure.